Driving safety is the primary consideration for a driver when driving and travelling on the road. The tire pressure is one of key factors of vehicle conditions, and has a critical influence on driving safety. A vehicle can run smoothly only with a normal tire pressure. An excessive or insufficient tire pressure may result in a punctured tire or a flat tire, which severely jeopardizes driving safety and even threatens the safety and wellbeing of passersby. Needless to say, monitoring a tire pressure for ensuring driving safety must be is attended with great importance. A conventional method for measuring a tire pressure can only be performed for a still vehicle, and changes of the tire pressure for a driving vehicle cannot be detected in real-time. That is, a driver may not immediately learn about abnormalities in a tire during driving, and may not accordingly take appropriate actions in the event of the abnormalities.
To better and more conveniently detect a tire pressure, various tire pressure detection devices, which can be installed to a tire, have been developed by associated manufacturers to enable a driver to learn about the changes of the tire pressure in real-time. The Taiwan Utility Model No. M335410 discloses a “Wireless Tire Pressure Detector”, as a built-in tire sensor. The disclosed tire pressure detector includes a sensor unit, and a gas nozzle unit integrated with the sensor unit. The sensor unit includes a housing, a circuit board disposed in the housing, and a gasket inserted at the housing. The housing has a gas intake, and a channel adjoining with the gas intake. The gasket is disposed at the gas intake and includes a connecting portion electrically connected to the circuit board. The gas nozzle unit includes a pipe member that may be utilized as an antenna, at least one washer accommodating around the pipe member, a cap screwed to one end of the pipe member, and at least one screw nut screwed to another end of the pipe member. As the fastening effect provided by the screw nut is greater than that of a conventional screw, the stability of the engagement between the sensor unit and the gas nozzle unit is improved.
The Taiwan Utility Model No. M405977 discloses a “Tire Pressure Sensor and Gas Nozzle Assembly”. The disclosed structure is formed by a gas nozzle, a tire pressure sensor, and a screw bolt fastening the gas nozzle and the tire pressure sensor. The gas nozzle includes a connecting portion which includes an outer adjustment surface. The tire pressure includes a housing, which has a connecting channel connected to the connecting portion of the gas nozzle. Further, the connecting channel includes an inner adjustment surface forming in a shape complementary to that of the outer adjustment surface. Through the outer adjustment surface and the inner adjustment surface, the connecting portion of the gas nozzle is merely allowed to rotate towards a predetermined direction relative to the connecting channel. As such, the tire pressure sensor and the gas nozzle are prohibited from arbitrary rotations when fastened by the screw bolt, so as to reduce complications when installing the tire pressure detector on a tire rim.
The above disclosures of M335410 and M405977 are both built-in tire pressure sensors that are installed to the inside of a tire to detect the tire pressure. A high temperature is generated by friction between a tire and the ground during a driving process. Under such high-temperature and high-pressure harsh operating environment in the tire, the tire pressure sensor requires a high level of air tightness to prevent dust or moisture from entering the housing and thus affecting operations of the sensor unit. Therefore, for the above built-in tire pressure sensor, the housing is completely sealed after assembling with the sensor unit and a battery to ensure the overall air tightness. This implies that, once electrical power of the battery is depleted, the tire pressure sensor/detector of the disclosures M335410 and M405977 can no longer operate and be utilized. Even when the sensor unit is functional and undamaged, a new tire sensor needs to be purchased, which not only results in an additional cost for a driver but also produces unnecessary wastes.